Presentation control device, game machine and program

ABSTRACT

A presentation control device includes: a first display unit which is a transmissive display unit; a transparent backlight formed of transparent material, provided relative to the first display unit opposite the viewing surface of the first display unit, and configured to emit light toward the first display unit; a light source configured to output object light to the transparent backlight where light from an object provided opposite the light emission plane of the transparent backlight is output toward the transparent backlight and the first display unit; and a display device including a controller configured to control the first display unit, the transparent backlight, and the light source so that light emitted from the transparent backlight shows an image on the first display unit, and so that the object light can pass through the transparent backlight and the first display unit and be output.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of InternationalApplication No. PCT/JP2015/086326, filed on Dec. 25, 2015, which claimspriority based on the Article 8 of Patent Cooperation Treaty from priorJapanese Patent Applications No. 2015-006234, filed on Jan. 15, 2015,the entire contents of which are incorporated herein by reference.

FIELD

The disclosure relates to a presentation control device, a game machineand a program.

BACKGROUND

An image presentation device may be equipped with: a transparent liquidcrystal panel that provides transmissive display in a transparentdisplay region; and an LCD with the display screen located behind thetransparent liquid crystal panel (refer to for example, Patent Document1).

Patent Document 1 Japanese Unexamined Patent Application Publication No.2014-61335

Technical Problem

A transmissive display unit such as a liquid crystal panel may beprovided on the front surface of a display device; in this case, thetransmissive display unit can only present images using the lightexiting from the display device. Therefore, in practical termspresenting a sufficiently bright image via both the transmissive displayunit and the display device can be quite challenging. Additionally,there are times when the transmissive display unit cannot expresscertain colors depending on the color of the image being presented onthe display device. For instance, the transmissive display unit isunable to show a blue image superimposed over a region where the displaydevice is presenting a red image. Accordingly, the device cannot providean image with superior visual effect.

SUMMARY

In a first embodiment, a presentation control device includes: a firstdisplay unit which is a transmissive display unit; a transparentbacklight formed of transparent material, provided relative to the firstdisplay unit opposite the viewing surface of the first display unit, andconfigured to emit light toward the first display unit; a light sourceconfigured to output object light to the transparent backlight wherelight from an object provided opposite the light emission plane of thetransparent backlight is output toward the transparent backlight and thefirst display unit; and a display device including a display controllerconfigured to control the first display unit, the transparent backlight,and the light source so that light emitted from the transparentbacklight shows an image on the first display unit, and so that theobject light can pass through the transparent backlight and the firstdisplay unit and be output. The presentation control device may beprovided with a presentation controller configured to control thedisplay controller on the basis of a command received to cause the firstdisplay unit to show an image with light emitted from the transparentbacklight, and to allow output of object light.

The presentation controller controls the display controller on the basisof the command received to cause the light emission state of thetransparent backlight to switch while the object light is output.

The presentation controller may control the display controller on thebasis of the command received to cause the first display unit to switchbetween a state of presenting an image thereon and a state of presentingan image from the object light by causing the transparent backlight toswitch between a state where the transparent backlight emits light and astate where the transparent backlight does not emit light while theobject light is output.

The transparent backlight may be configured to switch the intensity oflight emitted by the transparent backlight between a first lightintensity and a second light intensity greater than the first lightintensity; and the presentation controller controls the displaycontroller on the basis of the command received to cause the image shownon the first display unit and the image from the object light to bepresented simultaneously by setting the light emission intensity of thetransparent backlight to said first light intensity while the objectlight is output.

The presentation controller may control the display controller on thebasis of the command received to cause the light emission state of thetransparent backlight to switch while the object light is output.

The presentation controller may control the display controller on thebasis of the command received to allow the image shown on the firstdisplay unit and the image from the object light to be observedsubstantially at the same time by causing the transparent backlight toswitch between a state where the transparent backlight emits light and astate where the transparent backlight does not emit light at a rategreater than a predetermined rate while the object light is output.

The presentation controller may control the display controller on thebasis of the command received to cause the combination of the lightemission state of the transparent backlight and the content shown on thefirst display unit to vary while the object light is output.

The light source may emit light that illuminates the object; and thepresentation controller controls the display controller on the basis ofthe command received to control the light source.

The display device may be provided in a game machine, and the object mayinclude an accessory in the game machine.

The display device may further include a second display unit configuredto output image light based on light from the light source as objectlight; where the object is the second display unit; and the presentationcontroller controls the display controller on the basis of the commandreceived to cause an image to be shown on the second display unit.

The presentation controller controls the display controller on the basisof the command received to cause the image shown on the second displayunit to vary while causing an image to be shown on the first displayunit with light emitted from the transparent backlight.

The transparent backlight may include a light guide plate formed oftransparent material and including a light input surface, a light outputsurface facing the first display unit, the light guide plate configuredto cause light entering from the input surface to propagate therethroughand exit from the output surface; and a light source configured to emitlight that enters through the input surface into the light guide plate;wherein the presentation controller controls the display controller onthe basis of the command received to control the light emission state ofthe light source.

In a second embodiment, a game machine is provided with the abovepresentation control device, and the above display device.

In a third embodiment a program causes a computer to function as theabove presentation control device.

Note that the above summary does not list all the features of thepresent invention. Sub combinations of these sets of features are alsowithin the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic front view of a game machine 10 provided with adisplay device 100 according to one embodiment;

FIGS. 2A and 2B are schematic views of the configuration of a displaycomponent 80 provided in the display device 100;

FIG. 3 is a block diagram of a controller 30 and display device 100provided on a playfield 11;

FIGS. 4A, 4B, and 4C illustrate an image presented on the display device100;

FIGS. 5A and 5B illustrate the transparent liquid crystal panel 210 anda liquid crystal display 220 both showing an image;

FIG. 6 illustrates another example of control when simultaneouslypresenting an image 410 and an image 420;

FIG. 7 illustrates an example of the controller 30 and display device100 controlling presentation;

FIG. 8 is a schematic perspective view of a display component 880 and isan example of modifying a display component;

FIGS. 9A and 9B illustrate an image presented by the display component880;

FIGS. 10A and 10B are lateral cross-sectional views illustratinggenerally a transparent backlight 230;

FIGS. 11A and 11B illustrate examples of modifying a reflection surface1020;

FIG. 12 is a table expressing a relationship between pattern density andhaze, and how an image appears;

FIGS. 13A, 13B, and 13C illustrate example patterns for distributingprisms;

FIG. 14 is the lateral cross-sectional view of another modification tothe light guide plate 240;

FIG. 15 is the lateral cross-sectional view of another modification tothe light guide plate 240; and

FIG. 16 is the lateral cross-sectional view of another modification tothe light guide plate 240.

DETAILED DESCRIPTION

The present invention is described by way of describing an embodiment;however, the below-mentioned embodiment is in no way a limitation on thepresent invention. All the combinations of features described in theembodiment are not necessarily required for solving the technicalproblem addressed by the invention.

FIG. 1 is a schematic front view of a game machine 10 provided with adisplay device 100 according to one embodiment. The game machine 10 is apinball machine. The game machine 10 includes a playfield 11 that is themain game unit; a ball trough 12; an input unit 13; a display device100; a stationary gadget 15; moving gadget 16; and at least one prizetarget 18; and rails 17.

The playfield 11 takes up a majority of the game machine 10, from thetop portion to the center. The ball trough 12 and the input unit 13 areprovided below the playfield 11. The display device 100 is provided insubstantially the center of the playfield 11. The display device 100 isinstalled on the playfield 11 so that the front surface of the liquidcrystal panel faces the player. Note that the front is toward where theuser of the game machine 10 is located. In some cases the surfaceopposite the front is referred to as the rear surface.

The display device 100, a stationary gadget 15, a moving gadget 16, aprize target 18, and rails 17 are provided on the playfield 11. Thestationary gadget 15 and the moving gadget 16 are used for presentingthe game. The stationary gadget 15 is provided, for example, on thefront surface at the lower part of the playfield 11. The moving gadget16 is provided between the playfield 11 and the stationary gadget 15.Additionally, a is also provided on the playfield 11. Multiple obstaclepins and the like are also provided on the playfield 11 to guide thepinball.

The input unit 13 accepts rotary input from the player. The game machine10 launches the pinball with a certain force in response to the amountof rotation of the input unit 13. The launched pinball travels on theplayfield 11 falling between the multiple obstacle pins. As is laterdescribed, the playfield 11 is provided with a controller 30. Thecontroller 30 pays out a predetermined number of pinballs into the balltrough 12 in accordance with the prize associated with the prize target18 when it is detected that the pinball entered a prize target 18.

The display device 100 presents the state of play in accordance withcontrol signals from the presentation controller 300. The display device100 shows images of various patterns and video graphics and the like inaccordance with the state of the game.

FIGS. 2A and 2B are schematic views of the configuration of a displaycomponent 80 provided in the display device 100. FIG. 2A is a simplifiedperspective view of a display component 80; and FIG. 2B is a simplifiedlateral view of the display component 80.

The display device 100 is equipped with a transparent liquid crystalpanel 210, a transparent backlight 230, and a liquid crystal display220. The liquid crystal display 220 includes a liquid crystal panel 260and a backlight 270.

The transparent liquid crystal panel 210 is one example of atransmissive display unit. The transparent liquid crystal panel 210includes a front surface 211, which is the surface viewed and a rearsurface 212. The rear surface 212 is opposite the front surface 211. Thetransparent backlight 230 is provided opposite the front surface 211 ofthe transparent liquid crystal panel 210. The transparent backlight 230emits light toward the transparent liquid crystal panel 210. Thetransparent backlight 230 is a transparent surface light source.

The transparent backlight 230 includes a light guide plate 240, a lightsource 250 a, a light source 250 b, a light source 250 c, and a lightsource 250 d. The light guide plate 240 includes a light input surface243, a light output surface 241, a diffusion surface 242, and an endsurface 244. The diffusion surface 242 is opposite the output surface241. The input surface 243 and the end surface 244 are one of the sidesurfaces of the light guide plate 240. The input surface 243 isorthogonal to the diffusion surface 242 and the output surface 241. Theend surface 244 is opposite the input surface 243. The light guide plate240 is produced from a transparent material. For instance, the lightguide plate 240 may be molded from a resin that is transparent tovisible light, such as poly methyl methacrylate (PMMA), a polycarbonate,or a cycloolefin polymer. The light guide plate 240 is provided so thatthe output surface 241 faces the transparent liquid crystal panel 210.The output surface 241 is provided as the light emission surface of thetransparent backlight 230. Thus, the transparent backlight 230 isprovided so that the output surface 241 of the light guide plate 240faces the rear surface 212 of the transparent liquid crystal panel 210.

The suffixes for the light source 250 a, light source 250 b, lightsource 250 c, and light source 250 d will be omitted and the samecollectively referred to as the light source 250. The light source 250emits visible light. For example, the light source 250 substantiallyemits white light. The light source 250 is provided facing the inputsurface 243 of the light guide plate 240. As one example, the lightsource 250 may be a light emitting element such as an LED. The lightsource 250 is arranged so that the direction of maximum light emissiontherefrom is orthogonal to the input surface 243. To improve the lightuse efficiency, the light source 250 is preferably a light emittingelement that possesses directivity. A collimating lens may also bearranged between the input surface 243 and the light source 250 toimprove the directivity of light emitted from the light source 250.Projections may also be formed on the input surface 243 projectingtoward the light source 250; the projections function as the collimatinglens that improves the directivity of light emitted from the lightsource 250.

Light from the light source 250 enters the light guide plate 240 fromthe input surface 243. The light traveling through the light guide plate240 is totally reflected by the diffusion surface 242 and thereafterexits from the output surface 241; the light then enters the transparentliquid crystal panel 210 from the rear surface 212 thereof.

Thus, when the light source 250 is lit, the light guide plate 240transmits and scatters the light from the light source 250 therethrough;the light is then output toward the transparent liquid crystal panel 210and consequently illuminates the transparent liquid crystal panel 210.An image in accordance with the pattern of the amount of lighttransmitted in the transparent liquid crystal panel 210 is shown on thefront surface 211 of the transparent liquid crystal panel 210 via thelight from the light guide plate 240.

The liquid crystal panel 260 in the liquid crystal display 220 does notrequire substantially transparent material; beyond that, the liquidcrystal panel 260 has the same configuration as the transparent liquidcrystal panel 210. The liquid crystal panel 260 of the liquid crystaldisplay 220 includes a front surface 261 corresponding to the frontsurface 211, and a rear surface 262 corresponding to the rear surface212. The rear surface 262 is opposite the front surface 261. Note thatthe liquid crystal panel 260 is one example of a component providedopposite the transparent backlight 230, and more specifically, oppositeto the light emission plane of the transparent backlight 230. Thebacklight 270 is also one example of a light source; and specifically,the backlight 270 is a light source that outputs light from an object,i.e., image light which is one example of object light.

More specifically, the backlight 270 emits light that illuminates theliquid crystal panel 260 from the rear surface 262 of the liquid crystalpanel 260. That is, the backlight 270 allows image light that passesthrough the liquid crystal panel 260 and then toward the transparentbacklight 230 and the transparent liquid crystal panel 210 to be outputfrom the liquid crystal panel 260.

More specifically, the backlight 270 of the liquid crystal display 220includes a light output surface 271, and a rear surface 272. The rearsurface 272 is opposite the output surface 271. The backlight 270 mayemploy a light guide plate. The backlight 270 may be an edge-typebacklight similar to the transparent backlight 230. The transparentbacklight 230 may also be configured so that a light source such as acold cathode ray tube or LED are directly beneath the backlight. Thebacklight 270 may be provided so that the output surface 271 thereoffaces the rear surface 262 of the liquid crystal panel 260.

The liquid crystal panel 260 is illuminated by light emitted from thebacklight 270 when the backlight 270 is illuminated. An image inaccordance with the pattern of the amount of light transmitted in theliquid crystal panel 260 is shown on the front surface 261 of the liquidcrystal panel 260 by way of the light from the backlight 270. Thus, theliquid crystal panel 260 outputs image light on the basis of light fromthe backlight 270.

Here, when the backlight 270 is lit, the light from the backlight 270enters the light guide plate 240 from the diffusion surface 242 afterpassing through the liquid crystal panel 260. The light guide plate 240is produced from a resin material that is transparent to visible lightas above described. Therefore, the light from the backlight 270 thatenters the light guide plate 240 from the diffusion surface 242 passesthrough the light guide plate 240 as is, exits from the output surface241 toward the transparent liquid crystal panel 210, passes through thetransparent liquid crystal panel 210 and exits from the front surface211. Consequently, a user able to see the front surface 211 of thetransparent liquid crystal panel 210 is able to view an image presentedon the liquid crystal panel 260 from the front surface 211 of thetransparent liquid crystal panel 210.

FIG. 3 is a block diagram of a controller 30 and display device 100provided on a playfield 11; the controller 30 includes a main controller310 and a presentation controller 300. The display device 100 isprovided with a display controller 330; the transparent liquid crystalpanel 210; a light source controller 340; the transparent backlight 230which includes the light source 250 and the light guide plate 240; andthe liquid crystal display 220 which includes the liquid crystal panel260 and the backlight 270.

The presentation controller 300 controls the display device 100 inaccordance with commands from the main controller 310. For instance, themain controller 310 may output information representing the state of thegame to the presentation controller 300, directing the presentationcontroller 300 to provide a visual according to the state of the game.The presentation controller 300 controls presentation on the displaydevice 100 by controlling the display controller 330 on the basis ofinformation from the main controller 310. Note that the state of thegame may be, for instance, “Prize Winner” or “Grand Prize!”, or thelike. The presentation controller 300 controls the display controller330 in accordance with the state of the game.

The display controller 330 controls the transparent liquid crystal panel210, the transparent backlight 230, and the light source so that animage is shown on the transparent liquid crystal panel 210 using lightemitted from the transparent backlight 230; the display controller 330also controls the transparent liquid crystal panel 210, the transparentbacklight 230, and the light source so that image light from the liquidcrystal display 220 may pass through the transparent backlight 230 andthe transparent liquid crystal panel 210 and be output. Hereby, thedisplay device 100 may provide an image shown by the transparent liquidcrystal panel 210 and an image shown by the liquid crystal display 220simultaneously.

The display controller 330 also changes how light is emitted from thetransparent backlight 230 while causing the liquid crystal display 220to output image light. For example, the display controller 330 switchesthe transparent backlight 230 between emitting and not emitting lightwhile causing the liquid crystal display 220 to output image light.Hereby, the display controller 330 is able to switch between having thetransparent liquid crystal panel 210 present an image and having theimage displayed via image light from the liquid crystal display 220.

The transparent backlight 230 may also switch between a first lightintensity and a second light intensity greater than the first lightintensity that can be emitted therefrom. As an example, the light sourcecontroller 340 may change the duty cycle of the current supplied to thelight source 250 in accordance with control by the display controller330 to change the intensity of the light emitted from the transparentbacklight 230. The light source controller 340 may switch among afour-stage duty cycle such as, 0%, 30%, 60% and 100%. The light sourcecontroller 340 may continuously and consecutively switch the duty cycle.At this point the display controller 330 causes the liquid crystaldisplay 220 to output image light and selects a first light intensityfor the transparent backlight 230, whereby the image shown on thetransparent liquid crystal panel 210 and the image created from imagelight from the liquid crystal display 220 may be presentedsimultaneously. The second light intensity may be the maximum intensityof the backlight. The second light intensity may be the intensity at aduty cycle of 100%. In contrast, for instance, the second lightintensity may be greater than zero but less than the maximum intensity.For example, the second light intensity may correspond to a duty cycleof 30% or 60% or the like.

The display controller 330 also changes the intensity of light emittedfrom the transparent backlight 230 while causing the liquid crystaldisplay 220 to output image light. Hereby the display controller 330 maycontrol the transparent liquid crystal panel 210 so that the degree ofemphasis on the image presented on the transparent liquid crystal panel210 changes over time in relation to the image formed due to image lightfrom the liquid crystal display 220.

The display controller 330 may switch between causing the transparentbacklight 230 to emit light and to not emit light at greater than apredetermined rate while allowing the liquid crystal display 220 tooutput image light. This allows an image shown on the transparent liquidcrystal panel 210 and an image from image light from the liquid crystaldisplay 220 to be shown substantially at the same time. Theaforementioned predetermined rate for switching the transparentbacklight 230 may be, for instance, a video frame rate or the refreshrate of the transparent liquid crystal panel 210 or the liquid crystaldisplay 220.

The display controller 330 may change a combination of the lightemission state of the transparent backlight 230 and what is shown on thetransparent liquid crystal panel 210 while causing the liquid crystaldisplay 220 to output image light. For example, the display controller330 may vary a combination of the light emission intensity of thetransparent backlight 230 and the image shown on the transparent liquidcrystal panel 210 over time. The display controller 330 may further varythe content of what is shown on the liquid crystal display 220. Forexample, the display controller 330 may vary the image shown on theliquid crystal panel 260 while causing the transparent liquid crystalpanel 210 to display an image using light emitted from the transparentbacklight 230. For example, the display controller 330 may also vary acombination of the light emission intensity of the transparent backlight230, the image shown on the transparent liquid crystal panel 210, andthe image shown on the liquid crystal display 220 over time. The displaydevice 100 is thereby capable of providing a variety of highlyinteresting visuals.

Two transparent substrates are provided facing each other to createtransparent electrodes and a liquid crystal is provided fillingtherebetween to produce the transparent liquid crystal panel 210 in thedisplay device 100. The display controller 330 controls the voltageapplied to each portion of the liquid crystal layer by way of thetransparent electrodes. The display controller 330 controls the voltageapplied to each portion of the liquid crystal layer to vary theorientation of each portion of the liquid crystal layer; with this thetransparent liquid crystal panel 210 is able to change the state ofdifferent stages of light passing through each portion of the liquidcrystal layer. Turning on the transparent backlight 230 at this pointallows the transparent liquid crystal panel 210 to show an image inaccordance with the pattern that appears due to the difference in theamount of light passing through the transparent liquid crystal panel 210and exiting from the front surface 211. In contrast, the displaycontroller 330 controls the voltage applied to each portion of theliquid crystal layer to ensure that there is substantially no variationin the state of light passing through each portion of the liquid crystallayer. The display controller 330 also ensures that light substantiallypasses through the transparent liquid crystal panel 210 and is, for themost part, uniformly output from the front surface 211. That is, thedisplay controller 330 essentially renders the transparent liquidcrystal panel 210 transparent. Note that the transparent liquid crystalpanel 210 is referred to as being in the ON state when it presents animage, and in the OFF state when it is substantially transparent. Thetransparent backlight 230 is referred to as being in the ON state whenit is illuminated, and is in the OFF state when not illuminated.

The display controller 330 controls how an image is presented on theliquid crystal display 220. That is, the display controller 330 controlsthe backlight 270 and the liquid crystal panel 260 similar tocontrolling the transparent liquid crystal panel 210 and the transparentbacklight 230 to render the display unit 220 able to show an image. Morespecifically the display controller 330 turns on the backlight 270 andrenders the liquid crystal panel 260 able to shown an image.Additionally, the display controller 330 may prevent the liquid crystaldisplay 220 from showing an image by rendering the liquid crystal panel260 substantially non-transparent to light. The display controller 330may turn off the backlight 270 so that an image is not presented on theliquid crystal display 220. The liquid crystal display 220 is referredto as in the ON state when it is showing an image, and is referred to asbeing in the off state when it is not showing an image.

Simple examples of display by the display device 100 are described withreference to FIG. 4A through FIG. 6. FIGS. 4A, 4B, and 4C are schematicsof an image presented on the display device 100. FIG. 4A depicts thetransparent liquid crystal panel 210 showing an image while the liquidcrystal display 220 does not show an image. More specifically, thetransparent liquid crystal panel 210 is in the ON state, the transparentbacklight 230 is in the ON state, and the liquid crystal display 220 isin the OFF state. In this state the display device 100 can present theuser with the image 410 shown on the transparent liquid crystal panel210.

FIG. 4B depicts the liquid crystal display 220 showing an image whilethe transparent liquid crystal panel 210 does not show an image. Morespecifically, the transparent liquid crystal panel 210 is in the OFFstate, the transparent backlight 230 is in the OFF state, and the liquidcrystal display 220 is in the ON state. In this state the display device100 can present the user with the image 420 shown on the liquid crystaldisplay 220.

FIG. 4C depicts the transparent liquid crystal panel 210 and the liquidcrystal display 220 both showing an image. More specifically, thetransparent liquid crystal panel 210 is in the ON state, the transparentbacklight 230 is in the ON state, and the liquid crystal display 220 isin the ON state. Hereby, the display device 100 may present the userwith the image 410 shown on the transparent liquid crystal panel 210 andthe image 420 shown on the liquid crystal display 220 simultaneously.

The display controller 330 may switch the display device 100 among anyof the states in FIG. 4A, FIG. 4B, and FIG. 4C as is desired. Forexample, the display controller 330 may switch the display status of thedisplay device 100 between presenting the state in FIG. 4A andpresenting the state in FIG. 4B. The display controller 330 may alsoswitch the display status of the display device 100 between presentingthe state in FIG. 4A and presenting the state in FIG. 4C. The displaycontroller 330 may also switch the display status of the display device100 between presenting the state in FIG. 4A and presenting the state inFIG. 4C. The display controller 330 may also switch the display statusof the display device 100 from presenting the states in FIG. 4A, FIG.4B, and FIG. 4C in that order. Note that the order used to change thedisplay state is not particularly limited to the order described here.

FIGS. 5A and 5B illustrate the transparent liquid crystal panel 210showing an image together with the liquid crystal display 220: in FIG.5A the transparent liquid crystal panel 210 shows a low-luminance image;in FIG. 5B the transparent liquid crystal panel 210 shows ahigh-luminance image. In FIG. 5A and FIG. 5B, the transparent liquidcrystal panel 210 is in the ON state, the transparent backlight 230 isin the ON state, and the liquid crystal display 220 is in the ON state.The light emission intensity of the transparent backlight 230 in FIG. 5Bis greater than the light emission intensity of the transparentbacklight 230 in FIG. 5A.

In the case of FIG. 5A, the display controller 330 controls the lightsource controller 340 to set the light emission intensity of thetransparent backlight 230 to less than a predetermined intensity, sothat the image 420 is a higher luminance than the image 410. Hereby, thedisplay device 100 may emphasize the image 420 shown on the liquidcrystal display 220 over the image 410 shown by the transparent liquidcrystal panel 210 when presenting the same to the user. Taking intoaccount the luminance of the image displayed on the liquid crystaldisplay 220, the display controller 330 may control the light emissionintensity of the transparent backlight 230 so that the luminance of theimage 420 is greater than the luminance of the image 410.

In the case of FIG. 5B, the display controller 330 controls the lightsource controller 340 to set the light emission intensity of thetransparent backlight 230 to greater than a predetermined intensity, sothat the image 420 is a lower luminance than the image 410. Hereby, thedisplay device 100 may emphasize the image 410 shown on the transparentliquid crystal panel 210 over the image 420 shown on the liquid crystaldisplay 220 when presenting the same to the user. Taking into accountthe luminance of the image displayed on the liquid crystal display 220,the display controller 330 may control the light emission intensity ofthe transparent backlight 230 so that the luminance of the image 420 isless than the luminance of the image 410.

FIG. 6 illustrates another example of control when simultaneouslypresenting the image 410 and the image 420. The display controller 330controls the light source controller 340 to switch the transparentbacklight 230 very rapidly between being turned on or turned off. Therate for switching the backlight on and off may be greater than a videoframe rate. The switching rate may be greater than the refresh rate ofthe transparent liquid crystal panel 210 or the liquid crystal display220. To a person, the image 410 and the image 420 may appear to be shownsimultaneously by very rapidly switching the transparent backlight 230on and off.

FIG. 7 illustrates an example of the controller 30 and display device100 controlling presentation. The main controller 310 provides thepresentation controller 300 with a state signal representing the stateof the game in the game machine 10. The presentation controller 300determines what is to be presented depending on the state of the game.

Memory accessible by the presentation controller 300 storescorrespondence information that maps the game state to a presentationcode. The memory accessible by the presentation controller 300 alsostores correspondence information that maps the presentation code topresentation content from the display device 100. As illustrated in FIG.7, presentation content includes: the transparent liquid crystal panel210 in the ON or OFF state or the transparent liquid crystal panel 210showing an image; the duty cycle of the transparent backlight 230; andthe liquid crystal display 220 in the ON or OF state or the liquidcrystal display 220 showing an image.

The presentation controller 300 specifies a presentation code that isstored in association with a game state represented by the state signalobtained from the main controller 310. The presentation controller 300controls the display controller 330 on the basis of the presentationcontent stored in association with the presentation code specified.

When the presentation code is “1”, the presentation controller 300instructs the display controller 330 to place the transparent liquidcrystal panel 210 in the OFF state, and place the transparent backlight230 in the OFF state (i.e., to set the duty cycle to 0%) so that thegraphic 721 of a person is shown on the liquid crystal display 220.Hereby the display device 100 presents an image 701 of the graphic 721.

When the presentation code is “2”, the presentation controller 300instructs the display controller 330 to allow the transparent liquidcrystal panel 210 to show the graphic 712, and set the duty cycle of thetransparent backlight 230 to 30% so that the graphic 722 of a person isshown on the liquid crystal display 220. Hereby the display device 100presents image 702, which is a low-luminance version of the graphic 712superimposed on the graphic 722.

When the presentation code is “3”, the presentation controller 300instructs the display controller 330 to allow the transparent liquidcrystal panel 210 to show the graphic 713, and set the duty cycle of thetransparent backlight 230 to 60% so that the graphic 723 of a person isshown on the liquid crystal display 220. Hereby the display device 100presents image 703, which is a mid-luminance version of the graphic 713superimposed on the graphic 723.

When the presentation code is “4”, the presentation controller 300instructs the display controller 330 to allow the transparent liquidcrystal panel 210 to show the graphic 714, and set the duty cycle of thetransparent backlight 230 to 30% so that the graphic 724 of a person isshown on the liquid crystal display 220. Hereby the display device 100presents image 704, which is a low-luminance version of the graphic 714superimposed on the graphic 724.

When the presentation code is “5”, the presentation controller 300instructs the display controller 330 to allow the transparent liquidcrystal panel 210 to show the graphic 715, and set the duty cycle of thetransparent backlight 230 to 100% so that the graphic 725 of a person isshown on the liquid crystal display 220. Hereby the display device 100presents image 705, which is a maximum-luminance version of the graphic715 superimposed on the graphic 725.

The display device 100 may thus optically superimpose and present thepattern shown on the transparent liquid crystal panel 210 onto thepattern shown by the liquid crystal display 220; the display device 100is thus also capable of changing the degree of emphasis on thesuperimposing pattern displayed by the transparent liquid crystal panel210 over time. The display device 100 is thereby able to provide highlyinteresting visuals.

FIG. 8 is a schematic perspective view of a display component 880 and isan example of modifying a display component included in the displaydevice 100. The display component 880 includes an illuminated gadget800, in addition to the transparent liquid crystal panel 210, thetransparent backlight 230, and the liquid crystal display 220 that canbe found in the display component 80.

The illuminated gadget 800 is one example of an accessory. Theilluminated gadget 800 is a moving gadget. The illuminated gadget 800moves between appearing inserted between the transparent backlight 230and the liquid crystal display 220 and appearing withdrawn from betweenthe transparent backlight 230 and the liquid crystal display 220. Theilluminated gadget 800 includes a gadget unit 810 and one or more lightemitting bodies 820. The light emitting body 820 may be an LED or thelike. The display controller 330 controls the illuminated gadget 800 toappear inserted or withdrawn, and controls the emission state of thelight emitting bodies 820 on the basis of information received from thepresentation controller 300.

FIGS. 9A and 9B illustrate an image presented by the display component880; FIG. 9A depicts the liquid crystal display 220 showing an imagewhile the transparent liquid crystal panel 210 does not show an imagewith the illuminated gadget 800 active. More specifically, thetransparent liquid crystal panel 210 is in the OFF state, thetransparent backlight 230 is in the OFF state, the liquid crystaldisplay 220 is in the ON state, and the illuminated gadget 800 appearsinserted while the light emitting bodies 820 output light. In this statethe display device 100 can present the user with the image 420 shown onthe liquid crystal display 220, and the illuminated gadget 800, which isemitting light, at the same time.

FIG. 9B depicts the transparent liquid crystal panel 210 showing animage, the liquid crystal display 220 showing an image 900, and theilluminated gadget 800 active. More specifically, the transparent liquidcrystal panel 210 is in the ON state, the transparent backlight 230 isin the ON state, the liquid crystal display 220 is in the ON state, andthe illuminated gadget 800 appears inserted while the light emittingbodies 820 output light. Hereby, the display device 100 may present theuser with the image 900 shown on the transparent liquid crystal panel210, the image 420 shown on the liquid crystal display 220, and theilluminated gadget 800 which is emitting light, at the same time.

The display controller 330 may switch the display device 100 between thestates in FIG. 9A and FIG. 9B as is desired. Note that the exampledepicted in FIG. 9A, 9B are only combinations of the liquid crystaldisplay 220 in the ON state and the illuminated gadget 800 being active.The display controller 330 may add a combination where the liquidcrystal display 220 is in the OFF state, and switch to that combination.The display controller 330 may add a combination where the illuminatedgadget 800 is in the OFF state, and switch to that combination.

FIGS. 10A and 10B are lateral cross-sectional views illustratinggenerally a transparent backlight 230. The lateral cross-sectional viewis of the light guide plate 240 from the cross section vertical to theoutput surface 241 along the propagation direction of light entering theinput surface 243 orthogonally from the light source 250.

The diffusion surface 242 includes a plurality of prisms 1010. Theseprisms 1010 reflect the light entering from the input surface 243causing the light to be substantially uniformly output from the entireoutput surface 241; the prisms 1010 also ensure the light enterssubstantially orthogonal to the transparent liquid crystal panel 210.

The plurality of prisms 1010 is formed so that the prisms are lined upat a predetermined pitch along the propagation direction of incidentlight entering from the input surface 243. The prisms 1010 are roughlytriangular grooves formed in the diffusion surface 242; morespecifically the triangular grooves extend in a direction substantiallyorthogonal to the propagation direction of incident light from the inputsurface 243. The prisms 1010 include a reflection surface 1020 thatforms a predetermined angle with the diffusion surface 242. Thispredetermined angle is set in accordance with the propagation directionof the incident light and the direction light is to exit the light guideplate 240.

In the embodiment, incident light propagates roughly parallel to thediffusion surface 242, and the light guide plate 240 causes light toexit, on the whole, vertically to the output surface 241. Therefore, thereflection surfaces 1020 may be created to form an angle of 37° to 45°with the diffusion surface 242. Preferably the angle α (unit: degrees)of the reflection surfaces 1020, and in particular the angle α between areflection surface 1020 and the diffusion surface 242 is established tosatisfy the following criteria:

α<90−tan⁻¹(sqrt(n ²−1))  (1)

Here n is the refractive index of the light guide plate 240.Furthermore, a light emitting element in the light source 250 ispreferably selected so that the half angle β (unit: degrees) of lightemitted from the light source 250 satisfies the following criteria:

β<109.74n−155.06  (2)

For instance, when the light guide plate 240 is produced from a PMMAresin (where the refractive index n=1.49), α is less than 42.17° and βis less than 8.5°. In addition, when the light guide plate 240 isproduced from a polycarbonate (where the refractive index n=1.59), α isless than 38.97° and β is less than 19.4°.

Because in this case the light is incident on the reflection surfaces1020 at greater than the critical angle, the incident light is totallyreflected by the reflection surfaces 1020 as illustrated by the arrow1001. Therefore, the light guide plate 240 is able to inhibit incidentlight from the light source 250 from exiting via the diffusion surface242, and is able to control the amount of light not used forilluminating the transparent liquid crystal panel 210.

Preferably, greater than a certain viewing angle is guaranteed so that auser may see an image shown on the transparent liquid crystal panel 210even when viewing the display device 100 from a diagonal. In order toguarantee a viewing angle of 15° or greater, the angle α between thereflection surface 1020 and the diffusion surface 242 and the half angleβ of the light source 250 preferably satisfies the following conditions:

α<1.4924n+40.274  (3)

β<−0.0327n+7.5127  (4)

For instance, when the light guide plate 240 is produced from a PMMAresin (where the refractive index n=1.49), α is less than 42.5° and β isless than 7.46°. In addition, when the light guide plate 240 is producedfrom a polycarbonate (where the refractive index n=1.59), α is less than42.7° and β is less than 7.46°.

Adjacent prisms 1010 may also be formed to have a constant pitchtherebetween, so that the intensity of light exiting the output surface241 does not depend on location.

Another input surface may be created at the end surface 244 of the lightguide plate 240 in addition to the input surface 243. That is, the lightguide plate 240 may include two opposing input surfaces with a pluralityof prisms 1010 arranged therebetween. The light source 250 may alsoinclude a light emitting element that emits light that enters the lightguide plate 240 from the input surface 243; and a light emitting elementthat emits light that enters the light guide plate 240 from the endsurface 244. In this case, reflection surfaces are formed on bothsurfaces of each of the prisms 1010, i.e., on the prism surface towardthe input surface 243 and on the prism surface toward the end surface244. These reflection surfaces are formed to satisfy Formula (1) orFormula (3) relative to the diffusion surface 242, so that the incidentlight is totally reflected toward the output surface 241. The lightemitting element arranged facing the end surface 244 may, for example,possess a half angle that satisfies Formula (2) or Formula (4).

In the modification example, the light entering from the input surface243 and exiting from the output surface 241, and the light entering fromthe end surface 244 and exiting from the output surface 241 spread outrelative to a normal to the output surface 241 in mutually reverseorientations. Therefore, the viewing angle is larger than the exampledepicted in FIG. 3A.

In another modification example, the end surface 244 which faces theinput surface 243 of the light guide plate 240 may be a mirrored surfaceto reflect the light propagating inside the light guide plate 240 towardthe inside of the light guide plate 240. This modification achieves aneffect identical to those provided by the above-mentioned modificationexample.

FIG. 10B is a schematic of another example of modifying the light guideplate 240. In the modification example the input surface 243 is angledat, for instance, 45° relative to the diffusion surface 242. The lightentering the light guide plate 240 from the input surface 243 isincident on the diffusion surface 242 and the output surface 241 atroughly 45°, and is totally reflected whereby the light propagatesthrough the light guide plate 240. Here, the light traveling through thelight guide plate 240 and reaching a prism 1010 strikes the reflectionsurface 1020 with an incident angle that is less than the criticalangle. However, in this case, as illustrated by the arrow 1002, lightexiting from the reflection surface 1020 is refracted towards thediffusion surface 242; therefore, the light reenters the light guideplate 240 from a surface of the prism 1010 further away from the lightsource 250. Consequently, this prevents a loss in light intensity due tolight exiting from the diffusion surface 242 toward the rear surface.

FIGS. 11A and 11B illustrate an example of modifying a reflectionsurface 1020; FIG. 11A illustrates schematically an example of modifyinga reflection surface 1020. In this modification example, the reflectionsurface 1020 is formed from a plurality of flat surfaces 1100 a and flatsurfaces 1100 b; the angle of inclination of the reflection surface 1020relative to the diffusion surface 242 increases closer to the outputsurface 241. Alternatively, the reflection surface 1020 may be formed bya cylindrical surface that is recessed relative to the input surface 243and where the center thereof is flat relative to the output surface 241.This increases the directivity of the light output from the outputsurface 241.

FIG. 11A illustrates schematically another example of modifying areflection surface 1020. In this modification example, the reflectionsurface 1020 is formed from a plurality of flat surfaces 1100 c and flatsurfaces 1100 d; the angle of inclination of the reflection surface 1020relative to the diffusion surface 242 increases closer the outputsurface 241 so that the reflection surface 1020 becomes a bump inrelation to the input surface 243. Alternatively, the reflection surface1020 may be formed by a cylindrical surface that protrudes relative tothe input surface 243 and where the center thereof is flat relative tothe output surface 241. In this case, the viewing angle increasesbecause the light entering the light guide plate 240 is reflected by thereflection surface 1020.

FIG. 12 is a table 1200 created via visual inspection to express therelationship between pattern density and haze, and how an image appears.

Pattern density is the ratio of the area of the region on which theprisms 1010 are formed to the surface area taken up by the diffusionsurface 242. The pattern density is preferably less than an upper limitwhere a user may perceive an image due to light from the rear of thelight guide plate 240 via a transparent component or, through theunobstructed air when the transparent liquid crystal panel 210 is in thetransparent state. In contrast, the pattern density is preferablygreater than a lower limit that allows a user to perceive an image shownon the transparent liquid crystal panel 210 with light from the lightsource 250 when the transparent liquid crystal panel 210 is in the ONthe state.

Haze is the proportion of diffusion light to totally transmitted light.Alternatively, haze is preferably lower than an upper limit where theuser can perceive an image on the liquid crystal display 220 behind thetransparent liquid crystal panel 210 via a transparent component or theunobstructed air when the transparent liquid crystal panel 210 is in thetransparent state.

The left column in the table 1200 represents the pattern density of theprisms 1010, the middle column represents haze, and the right columnrepresents the results of the visual inspection. In the experiment asingle tube type white LED (LP-3020H196W) was used as a light sourcecorresponding to the backlight 270. Haze was measured using a haze meterHM-150 L2 (manufactured by the Murakami Color Research Laboratory). Anobject illuminated via the light guide plate 240 and the transparentliquid crystal panel 210 in the transparent state was visuallyinspected; the result was labeled “OK” when it was perceived that therewas a transparent component in front of the object, and labeled “NG”when it was perceived that there was a non-transparent component infront of the object.

The visual inspection results were labeled “NG” when the pattern densityexceeded 30% or haze exceeded 28% as illustrated in the table 1200.Thus, preferably, the prisms 1010 are formed so that the pattern densityis less than or equal to 30.0%. Alternatively, preferably the prisms1010 are formed so that haze is less than or equal to 28%.

FIGS. 13A, 13B, and 13C illustrate example patterns for distributingprisms; FIG. 13A, FIG. 13B, and FIG. 13C each illustrate an examplepattern for distributing prisms when the pattern density is less than orequal to 30.0% and the haze is less than or equal to 28%. In thisexample, the length W of each of the prisms 1010 along the propagationdirection of the incident light is 27.5 μm; and the length L of each ofthe prisms 1010 in a direction orthogonal to the propagation directionof the incident light is 55 μm. For instance, each of the prisms 1010 isdistributed with the pitch of 50 μm and staggered at 50 μm when thepattern density is roughly 30.0% and haze is roughly 28%, as illustratedby the distribution pattern 1301 depicted in FIG. 13A.

The prisms 1010 may also be distributed in a lattice as illustrated bythe distribution pattern 1302 depicted in FIG. 13B. When distributed ina lattice, the prisms 1010 may be distributed so that the pitch is 100μm.

The prisms 1010 may also be distributed so that the number of prisms1010 is different in each column along a direction orthogonal to theinput surface 243 as illustrated by the distribution pattern 1303depicted in FIG. 13C.

FIG. 14 is the lateral cross-sectional view of another modification tothe light guide plate 240. In this example modification of the lightguide plate 240 a trapezoid pattern is formed in the diffusion surface242; the pattern protrudes from the diffusion surface 242 toward theliquid crystal display 220. The input surface 243 is orthogonal to thediffusion surface 242 and the output surface 241. A plurality oftrapezoid prisms 1410 is created on the diffusion surface 242. Theseprisms 1410 reflect the light entering from the input surface 243causing the light to be substantially uniformly output from the entireoutput surface 241; the prisms 1410 also ensure that the light enterssubstantially orthogonal to the transparent liquid crystal panel 210.

The trapezoid prisms 1410 are lined up at a predetermined pitch alongthe propagation direction of incident light entering from the inputsurface 243. The prisms 1410 are formed in the diffusion surface 242 astrapezoid protrusions along a direction substantially orthogonal to thepropagation direction of incident light from the input surface 243.Preferably the inclined surface 1400 on the side of the prism 1410 farfrom the light source 250 is created to totally reflect lightpropagating within the light guide plate 240 toward the output surface241 when the light strikes the diffusion surface 242 at a small angle asdepicted by the arrow 1401. Moreover, preferably the inclined surface1400 is also formed so that when the light propagating through the lightguide plate 240 strikes the diffusion surface 242 at a given largerangle, even if the light is not totally reflected, the light output tothe outside of the light guide plate 240 by the inclined surface 1400 isalso refracted by the inclined surface 1400 toward the diffusion surface242 as illustrated by the arrow 1402. The inclined surface 1400 may, forexample, form an angle of 45° with the diffusion surface 242. Theinclined surface on the side of the prism 1410 near the light source 250is not particularly limited, and may be an angle that simplifies moldingthe light guide plate 240.

The prisms 1410 are preferably formed so the pattern density is lessthan or equal to 30%, or haze is less than or equal to 28% in thismodification example. For instance, the prisms 1410 may be formed sothat the width of the prism 1410 along the propagation direction ofincident light is 30 μm, and the gap between two adjacent prisms 1410 is100 μm.

FIG. 15 is the lateral cross-sectional view of another modification tothe light guide plate 240. In this modification example, the diffusionsurface 242 on the light guide plate 240 is a flat surface so that lightpropagating through the light guide plate 240 is totally reflected; thediffusion service 242 includes a plurality of trapezoid prisms formed onthe output surface 241. In this modification example, the input surface243 may be formed at an angle of 45° with the diffusion surface 242;hereby, the majority of the light from the light source 250 propagatesthrough the light guide plate 240 at an angle where the light is totallyreflected at the diffusion surface 242. The light source 250 is alsoarranged so that the direction of maximum light emission therefrom isorthogonal to the input surface 243. In this situation, the lightentering the light guide plate 240 from the input surface 243 isincident on the diffusion surface 242 and the output surface 241 atroughly 45°, and is totally reflected whereby the light propagatesthrough the light guide plate 240. A plurality of trapezoid prisms 1510is formed on the output surface 241 to output incident light totallyreflected by the diffusion surface 242 toward the transparent liquidcrystal panel 210.

The trapezoid prisms 1510 are lined up at a predetermined pitch alongthe propagation direction of incident light entering from the inputsurface 243. The prisms 1510 are formed in the output surface 241 astrapezoid protrusions along a direction substantially orthogonal to thepropagation direction of incident light from the input surface 243.Preferably an inclined surface 1500 on the side of the prism 1510 farfrom the light source 250 is created so that light propagating throughthe light guide plate 240 is refracted at the inclined surface 1500 tothereby become light oriented in a direction substantially orthogonal tothe output surface 241, as depicted by the arrow 1501. The inclinedsurface 1500 may, for example, form an angle of 70° to 80° with theoutput surface 241. The inclined surface on the side of the prism 1510near the light source 250 is not particularly limited, and may be anangle that simplifies molding the light guide plate 240.

The prisms 1510 are preferably formed so the pattern density is lessthan or equal to 30%, or haze is less than or equal to 28% in thismodification example. For instance, the prisms 1510 may be formed sothat the width of the prism 1510 along the propagation direction ofincident light is 30 μm, and the gap between two adjacent prisms 1510 is100 μm.

FIG. 16 is the lateral cross-sectional view of another modification tothe light guide plate 240. In this modification example, a saw-likepattern is formed in the diffusion surface 242 of the light guide plate240. In this modification example the diffusion surface 242 includes atriangular pattern distributed periodically at a predetermined pitchalong the propagation direction of incident light entering from theinput surface 243. The patterns 1610 are formed from a relatively widefirst reflection surface 1620 a that increases the thickness of thelight guide plate 240 further away from the light source 250 and asecond reflection surface 1620 b, thinner than the first reflectionsurface 1620 a, that decreases the thickness of the light guide plate240 further from the light source 250. The first reflection surface 1620a forms and angle of 10° to 20° with the output surface 241 so thatlight propagating through the light guide plate 240 is totallyreflected. Whereas, the second reflection surface 1620 b forms thelarger angle with the output surface 241 than the first reflectionsurface 1620 a (e.g., 70° to 80°). The second reflection surface 1620 bis formed so that light reflected by the first reflection surface 1620 aand then entering the second reflection surface 1620 b is totallyreflected and oriented in a direction roughly perpendicular to theoutput surface 241.

A louver film may be placed between the light guide plate 240 and theliquid crystal display 220; the louver film blocks light enteringdiagonally. Note that the louver film may also be placed between thelight guide plate 240 and the illuminated gadget 800 when configuringthe display component 880 depicted in FIG. 8; the louver film blockslight entering diagonally.

The louver film is one example of a direction-selective light shieldingcomponent. The louver film is created by arranging a plurality ofnon-transparent material at a predetermined pitch along the propagationdirection of light from the light source 250 inside a sheet-likematerial produced from a transparent material such as a transparentresin. The plurality of non-transparent materials is orthogonal to asurface facing the light guide plate 240, and extends along a directionintersecting with the propagation direction of light from the lightsource 250. The plurality of non-transparent materials preferablyextends along a direction roughly parallel to the direction that theprisms 1010 extend. The predetermined pitch may be the width from theend part of the non-transparent material in the louver film facing thelight guide plate 240 to the end part facing the liquid crystal display220 or the illuminated gadget 800; the predetermined pitch may also beless than the aforementioned width. Therefore, even when light from thelight source 250 exits from the diffusion surface 242 of the light guideplate 240, the light is blocked by the non-transparent material whichprevents that light from illuminating the liquid crystal display 220 orthe illuminated gadget 800. In contrast, the non-transparent material inthe louver film does not block light entering perpendicular to thesurface of the liquid crystal display 220 or the illuminated gadget 800.Therefore, light emitted from the backlight 270 or the illuminatedgadget 800 that enters the louver film can pass through the light guideplate 240 and the transparent liquid crystal panel 210 to reach theuser. As a result, the user is able to view an image on the liquidcrystal display 220 or see light from the illuminated gadget 800 whilethe transparent liquid crystal panel 210 is in the transparent state andthe liquid crystal display 220 shows an image, or while the lightemitting element in the illuminated gadget 800 is turned on even whenthe louver film is provided on the front surface of the liquid crystaldisplay 220 or the illuminated gadget 800.

Light from the light source 250 may leak toward the rear surface of thelight guide plate 240. This light may form an angle with a normal lineto the diffusion surface 242 of the light guide plate 240. Preferably,the light guide plate 240 is configured so that the intensity of thelight leaking in the aforementioned manner at an angle greater than theviewing angle of the louver film is twice or more the intensity of thelight leaking at less than the viewing angle of the louver film. Lightfrom the light source 250 may leak toward the rear surface of the lightguide plate 240. This light may form an angle with a normal line to thediffusion surface 242 of the light guide plate 240. Alternatively, thelight guide plate 240 may be configured so that the intensity of thelight leaking in the aforementioned manner at an angle greater than 45°is twice or more the intensity of the leaking light which forms an angleof less than 45°.

The modification example prevents the light exiting from the rear of thelight guide plate 240 from illuminating an object behind the light guideplate. The modification thus prevents the light from the transparentbacklight 230 that strikes and reflects from an object behind thetransparent backlight from being output toward the user, when, forexample, the transparent backlight 230 is at the maximum luminance.

A polarizer that allows polarized light with a polarization planeoriented in a predetermined direction to pass therethrough may be placedbetween the liquid crystal display 220 or the illuminated gadget 800 andthe light guide plate 240. The polarizer may be provided in place of orin addition to the louver film. The polarizer is arranged so thatpreferably the transmission axis of the polarizer is the same directionas the transmission axis of the polarization plate on the rear surfaceof the transparent liquid crystal panel 210. The polarizer attenuatesthe light exiting the transparent backlight 230 from the diffusionsurface 242 and passing therethrough. Additionally, reflection ordispersion at the liquid crystal display 220 or the illuminated gadget800 changes the polarization direction of this light, the polarizerfurther attenuates the light before the same re-enters the light guideplate 240. It is thereby possible to prevent light exiting from the rearof the light guide plate 240 from illuminating an object behind thelight guide plate. The modification thus prevents the light from thetransparent backlight 230 that strikes and reflects from an objectbehind the transparent backlight from being output toward the user,when, for example, the transparent backlight 230 is at the maximumluminance.

The game machine 10 is one example of a game machine. In addition to thepinball machine, the game machine may be a slot machine.

The processes described as operations of the presentation controller 300in the above description may be implemented by a processor controllingthe other hardware provided to the game machine 10 or the display device100 in accordance with a program. That is, a processor may operate inaccordance with a program to control pieces of hardware, whereby theprocesses described in relation to the presentation controller 300 areimplemented by operation of each piece of hardware including theprocessor and memory and the like in cooperation with a program. Thatis, the aforementioned processes may be implemented on a computer, so tospeak. The computer may load a program for controlling execution of theabove-described processes, operate according to the loaded program, andthereby execute the aforementioned processes. The computer may load theaforementioned program from a computer readable medium storing theprogram.

The present invention is described by way of the embodiments; however,the technical scope of the present invention is not limited to theabove-described embodiments. It is obvious to a person skilled in theart that the above described embodiments can be modified or improved invarious ways. The scope of the claims makes it clear whether such kindsof modifications or improvements to the embodiments are within thetechnical scope of the present invention.

It should be noted that unless explicitly stated with terms such as“before”, “prior to”, and the like, and unless the output of a priorprocess is used in a subsequent process, the sequence of execution ofoperations, procedures, steps, and stages within the devices, systems,programs, and methods expressed in the scope of the claims, thespecification, and the drawings, may be executed any order as desired.The terms “first”, “next”, and the like are used for convenience whendescribing operational flows within the scope of the claims, thespecification, and in the drawings, and does not mean that execution inthis order is required.

1. A presentation control device comprising: a first display unit whichis a transmissive display unit; a transparent backlight formed oftransparent material, provided relative to the first display unitopposite the viewing surface of the first display unit, and configuredto emit light toward the first display unit; a light source configuredto output object light to the transparent backlight where light from anobject provided opposite the light emission plane of the transparentbacklight is output toward the transparent backlight and the firstdisplay unit; a display device controlled by the presentation controldevice, the display device including a display controller configured tocontrol the first display unit, the transparent backlight, and the lightsource so that light emitted from the transparent backlight shows animage on the first display unit, and so that the object light can passthrough the transparent backlight and the first display unit and beoutput; and a presentation controller configured to control the displaycontroller on the basis of a command received to cause the first displayunit to show an image with light emitted from the transparent backlight,and to allow output of object light.
 2. The presentation control deviceaccording to claim 1, wherein the presentation controller controls thedisplay controller on the basis of the command received to cause thelight emission state of the transparent backlight to switch while theobject light is output.
 3. The presentation control device according toclaim 1, wherein the presentation controller controls the displaycontroller on the basis of the command received to cause the firstdisplay unit to switch between a state of presenting an image thereonand a state of presenting an image from the object light by causing thetransparent backlight to switch between a state where the transparentbacklight emits light and a state where the transparent backlight doesnot emit light while the object light is output.
 4. The presentationcontrol device according to claim 1, wherein the transparent backlightis configured to switch the intensity of light emitted by thetransparent backlight between a first light intensity and a second lightintensity greater than the first light intensity; and the presentationcontroller controls the display controller on the basis of the commandreceived to cause the image shown on the first display unit and theimage from the object light to be presented simultaneously by settingthe light emission intensity of the transparent backlight to said firstlight intensity while the object light is output.
 5. The presentationcontrol device according to claim 1, wherein the presentation controllercontrols the display controller on the basis of the command received tocause the light intensity of light emitted from the transparentbacklight to vary while the object light is output.
 6. The presentationcontrol device according to claim 1, wherein the presentation controllercontrols the display controller on the basis of the command received toallow the image shown on the first display unit and the image from theobject light to be observed substantially at the same time by causingthe transparent backlight to switch between a state where thetransparent backlight emits light and a state where the transparentbacklight does not emit light at a rate greater than a predeterminedrate while the object light is output.
 7. The presentation controldevice according to claim 1, wherein the presentation controllercontrols the display controller on the basis of the command received tocause the combination of the light emission state of the transparentbacklight and the content shown on the first display unit to vary whilethe object light is output.
 8. The presentation control device accordingto claim 1, wherein the light source emits light that illuminates theobject; and the presentation controller controls the display controlleron the basis of the command received to control the light source.
 9. Thepresentation control device according to claim 8, wherein the displaydevice is provided in a game machine; and the object includes anaccessory in the game machine.
 10. The presentation control deviceaccording to claim 1 with the display device further comprising: asecond display unit configured to output image light based on light fromthe light source as object light; where the object is the second displayunit; and the presentation controller controls the display controller onthe basis of the command received to cause an image to be shown on thesecond display unit.
 11. The presentation control device according toclaim 10, wherein the presentation controller controls the displaycontroller on the basis of the command received to cause the image shownon the second display unit to vary while causing an image to be shown onthe first display unit with light emitted from the transparentbacklight.
 12. The presentation control device according to claim 1,wherein the transparent backlight includes: a light guide plate formedof transparent material and including a light input surface, a lightoutput surface facing the first display unit, the light guide plateconfigured to cause light entering from the input surface to propagatetherethrough and exit from the output surface; and a light sourceconfigured to emit light that enters through the input surface into thelight guide plate; wherein the presentation controller controls thedisplay controller on the basis of the command received to control thelight emission state of the light source.
 13. A game machine comprising:a presentation control device according to claim 1; and a displaydevice.
 14. A program causing a computer to function as a presentationcontrol device according to claim 1.